Role of melatonin in carcinogenesis and metastasis: From mechanistic insights to intermeshed networks of noncoding RNAs.

In recent years, seminal studies have been devoted to unraveling the puzzling mysteries associated with the cancer preventive/inhibitory role of melatonin. Our current knowledge of the translational mechanisms and the detailed structural insights have highlighted the characteristically exclusive role of melatonin in the inhibition of carcinogenesis and metastatic dissemination. This mini-review outlines recent discoveries related to mechanistic role of melatonin in prevention of carcinogenesis and metastasis. Moreover, another exciting facet of this mini-review is related to phenomenal breakthroughs linked with regulation of noncoding RNAs by melatonin in wide variety of cancers.

Pomegranate extract inhibits migration and invasion of oral cancer cells by downregulating matrix metalloproteinase-2/9 and epithelial-mesenchymal transition.

Discovering drug candidates for the modulation of metastasis is of great importance in inhibiting oral cancer malignancy. Although most pomegranate extract applications aim at the antiproliferation of cancer cells, its antimetastatic effects remain unclear, especially for oral cancer cells. The aim of this study is to evaluate the change of two main metastasis characters, migration and invasion of oral cancer cells. Further, we want to explore the molecular mechanisms of action of pomegranate extract (POMx) at low cytotoxic concentration. We found that POMx ranged from 0 to 50 µg/mL showing low cytotoxicity to oral cancer cells. In the case of oral cancer HSC-3 and Ca9-22 cells, POMx inhibits wound healing migration, transwell migration, and matrix gel invasion. Mechanistically, POMx downregulates matrix metalloproteinase (MMP)-2 and MMP-9 activities and expressions as well as epithelial-mesenchymal transition (EMT) signaling. POMx upregulates extracellular signal-regulated kinases 1/2 (ERK1/2), but not c-Jun N-terminal kinase (JNK) and p38 expression. Addition of ERK1/2 inhibitor (PD98059) significantly recovered the POMx-suppressed transwell migration and MMP-2/-9 activities in HSC-3 cells. Taken together, these findings suggest to further test low cytotoxic concentrations of POMx as a potential antimetastatic therapy against oral cancer cells.

Regulation of signaling pathways by ß-elemene in cancer progression and metastasis.

Entry of ß-elemene into various phases of clinical trials advocates its significance as a premium candidate likely to gain access to mainstream medicine. Based on the insights gleaned from decades of research, it seems increasingly transparent that ß-elemene has shown significant ability to modulate multiple cell signaling pathways in different cancers. We partition this multicomponent review into how ß-elemene strategically modulates various signal transduction cascades. We have individually summarized regulation of tumor necrosis factor related apoptosis-inducing ligand, signal transducers and activators of transcription, transforming growth factor/SMAD, NOTCH, and mammalian target of rapamycin pathways by ß-elemene. Last, we will discuss the results of clinical trials of ß-elemene and how effectively we can use these findings to stratify patients who can benefit most from ß-elemene.

Curcumin on the "flying carpets" to modulate different signal transduction cascades in cancers: Next-generation approach to bridge translational gaps.

Curcumin, a bioactive and pharmacologically efficient component isolated from Curcuma longa has attracted considerable attention because of its ability to modulate diverse cellular and physiological pathways. WNT, TGF/SMAD, NOTCH, and SHH are fundamentally different signaling cascades, but their choreographed activation is strongly associated with cancer development and progression. In this review we have attempted to set spotlight on regulation of different cell signaling pathways by curcumin in different cancers. We partition this multi-component review into in-depth biological understanding of various signal transduction cascades and how curcumin targets intracellular signal transducers of deregulated pathways to inhibit cancer development and progression. Rapidly broadening landscape of both established and candidate oncogenic driver mutations identified in different cancers is a major stumbling block in the standardization of drugs having significant clinical outcome. Intra and inter-tumor heterogeneity had leveraged the complexity of therapeutic challenges to another level. Multi-pronged approach and molecularly guided treatments will be helpful in improving the clinical outcome.

Inclusion of a pH-responsive amino acid-based amphiphile in methotrexate-loaded chitosan nanoparticles as a delivery strategy in cancer therapy.

The encapsulation of antitumor drugs in nanosized systems with pH-sensitive behavior is a promising approach that may enhance the success of chemotherapy in many cancers. The nanocarrier dependence on pH might trigger an efficient delivery of the encapsulated drug both in the acidic extracellular environment of tumors and, especially, in the intracellular compartments through disruption of endosomal membrane. In this context, here we reported the preparation of chitosan-based nanoparticles encapsulating methotrexate as a model drug (MTX-CS-NPs), which comprises the incorporation of an amino acid-based amphiphile with pH-responsive properties (77KS) on the ionotropic complexation process. The presence of 77KS clearly gives a pH-sensitive behavior to NPs, which allowed accelerated release of MTX with decreasing pH as well as pH-dependent membrane-lytic activity. This latter performance demonstrates the potential of these NPs to facilitate cytosolic delivery of endocytosed materials. Outstandingly, the cytotoxicity of MTX-loaded CS-NPs was higher than free drug to MCF-7 tumor cells and, to a lesser extent, to HeLa cells. Based on the overall results, MTX-CS-NPs modified with the pH-sensitive surfactant 77KS could be potentially useful as a carrier system for intracellular drug delivery and, thus, a promising targeting anticancer chemotherapeutic agent.

Association between breast cancer and tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) gene 1595C/T SNP in a Pakistani population.

AIM OF THE STUDY: TRAIL-mediated signalling has emerged as an extensively studied biological mechanism reported to differentially induce apoptosis in cancer cells. However, overwhelmingly increasing experimentally verified data is shedding light on resistance against TRAIL-induced apoptosis in cancer cells. Moreover, genetic and epigenetic mutations also exert effects on the functionality of TRAIL and its receptors. In this study we investigated the association between breast cancer and polymorphisms in tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) in a Pakistani Population. MATERIAL AND METHODS: Genotyping for TRAIL gene 1595 C/T polymorphism was done for 363 breast cancer patients and 193 age- and sex-matched healthy controls. DNA was extracted using standard organic methods. PCR-RFLP analysis was done for C/T polymorphism at position 1595 in exon 5 of the TRAIL gene using site-specific primers and restriction enzyme. The results were statistically evaluated by SPSS14. RESULTS: In this study, CC homozygotes were 46.3% in patients and 49.7% in controls, p = 0.729 with OR value 0.8705 (95% CI: 0.6137-1.2348). CT was statistically insignificant, p = 0.837 with OR value 0.9242 (95% CI: 0.6494-1.3154). However, the minor allele or risk allele genotype TT had a higher percentage among breast cancer patients (12.1%) than in the control group (6.7%). Since there was a statistically insignificant difference (p = 0.212, OR value 1.9098 with 95% CI 1.0019 to 3.6406) of TT genotype between the two groups, the contrastingly higher percentage of TT genotype in breast cancer patients seems to be a risk factor for the disease. Moreover, the frequency of minor allele T was also found to be higher in the patients (0.329) than in the controls (0.285). CONCLUSIONS: The TRAIL gene 1595 C/T SNP has a contradictory role in cancer development in different populations. In our population group although the percentage of homozygous risk allele TT was higher in patients it was statistically non-significant. The raised T allele and TT genotype in patients may suggest its association with breast cancer in the Pakistani population.

Getting personal with prostate cancer: adding new pieces to an incomplete jigsaw puzzle.

Prostate cancer is a multifaceted molecular anomaly that is insurmountable to date because of the orchestrated network of negative regulators that drive carcinogenesis. A substantial fraction of information has been added that gives yet an unclear snapshot of therapeutic interventions in prostate cancer. Increasing sophisticated interpretations point towards some important aspects of prostate cancer aggressiveness like microRNAs, prostate cancer stem cells and TRAIL (tumor necrosis factor-related apoptosis-inducing ligand) refractoriness. In this review, we will evaluate the push and pull between oncomirs and tumor suppressors in tipping the scales of cancer. Furthermore, multicomponent rational drug designs with a claim to overcome stumbling blocks will be discussed. Translation of the outcomes achieved in the understanding of carcinogenesis at the patient's bedside is possibly the principal challenge in cancer research.

Pomegranate Extract (POMx) Induces Mitochondrial Dysfunction and Apoptosis of Oral Cancer Cells.

The anticancer effect of pomegranate polyphenolic extract POMx in oral cancer cells has rarely been explored, especially where its impact on mitochondrial functioning is concerned. Here, we attempt to evaluate the proliferation modulating function and mechanism of POMx against human oral cancer (Ca9-22, HSC-3, and OC-2) cells. POMx induced ATP depletion, subG1 accumulation, and annexin V/Western blotting-detected apoptosis in these three oral cancer cell lines but showed no toxicity to normal oral cell lines (HGF-1). POMx triggered mitochondrial membrane potential (MitoMP) disruption and mitochondrial superoxide (MitoSOX) generation associated with the differential downregulation of several antioxidant gene mRNA/protein expressions in oral cancer cells. POMx downregulated mitochondrial mass, mitochondrial DNA copy number, and mitochondrial biogenesis gene mRNA/protein expression in oral cancer cells. Moreover, POMx induced both PCR-based mitochondrial DNA damage and γH2AX-detected nuclear DNA damage in oral cancer cells. In conclusion, POMx provides antiproliferation and apoptosis of oral cancer cells through mechanisms of mitochondrial impairment.

Vitamin C as an Anticancer Agent: Regulation of Signaling Pathways.

Treatment options for effective treatment of cancer with minimum off-target effects and maximum clinical outcomes have remained overarching goals in the clinical oncology. Vitamin C has remained in the shadows of controversy since the past few decades; burgeoning evidence has started to shed light on wide-ranging anticancer effects exerted by Vitamin C to induce apoptosis in drug-resistant cancer cells, inhibit uncontrolled proliferation of the cancer cells and metastatic spread. Landmark achievements in molecular oncology have ushered in a new era, and researchers have focused on the identification of oncogenic pathways regulated by Vitamin C in different cancers. However, there are visible knowledge gaps in our understanding related to the ability of Vitamin C to modulate a myriad of transduction cascades. There are scattered pieces of scientific evidence about promising potential of Vitamin C to regulate JAK-STAT, TGF/SMAD, TRAIL and microRNAs in different cancers. However, published data is insufficient and needs to be investigated comprehensively to enable basic and clinical researchers to reap full benefits and promote result-oriented transition of Vitamin C into various phases of clinical trials. In this review, we will emphasize on available evidence related to the regulation of oncogenic cell signaling pathways by Vitamin C in different cancers. We will also highlight the conceptual gaps, which need detailed and cutting-edge research.

CS5931, A Novel Marine Polypeptide, Inhibits Migration and Invasion of Cancer Cells Via Interacting with Enolase 1.

BACKGROUND: CS5931, a novel marine peptide, was extracted and purified from the sea squirt Ciona savignyi. Our previous studies showed that recombinant CS5931 can significantly inhibit tumor growth both in vitro and in vivo. However, its molecular targets have not been elucidated. METHODS: The target of the recombinant CS5931 was identified by pull-down/SDS-PAGE/MS approaches and confirmed by Western blot and surface plasmon resonance analysis. Transwell experiments were used to detect whether the recombinant CS5931 inhibited cancer migration and invasion via enolase 1. Dot blotting analysis was used to detect the effect of CS5931 on the interaction of enolase 1 and plasminogen, as well as enolase 1 and uPA/uPAR. RESULTS: Enolase 1 was identified as the molecular target interacting with the recombinant CS5931. Transwell experiment showed that the recombinant CS5931 was able to inhibit migration and invasion of HCT116 cells and enolase 1 overexpression reversed the effects of the recombinant CS5931 on migration and invasion of cancer cells. Dot blotting analysis revealed that the recombinant CS5931 interfered with the interaction among enolase 1 and plasminogen as well as enolase 1 and uPA/uPAR. CONCLUSION: Our present study showed that the recombinant CS5931 could inhibit tumor invasion and matastasis via interacting with enolase 1, suggesting that the new marine polypeptide CS5931 possesses the potential to be developed as a novel anticancer agent.

Natural Products Mediated Regulation of Oxidative Stress and DNA Damage in Ultraviolet Exposed Skin Cells.

Data obtained through high-throughput technologies have gradually revealed that a unique stratified epithelial architecture of human skin along with the antioxidant-response pathways provided vital defensive mechanisms against UV radiation. However, it is noteworthy that skin is a major target for toxic insult by UV radiations that can alter its structure and function. Substantial fraction of information has been added into the existing pool of knowledge related to natural products mediated biological effects in UV exposed skin cells. Accumulating evidence has started to shed light on the potential of these bioactive ingredients as protective natural products in cosmetics against UV photodamage by exerting biological effects mainly through wide ranging intracellular signalling cascades of oxidative stress and modulation of miRNAs. In this review, we have summarized recently emerging scientific evidences addressing underlying mechanisms of UV induced oxidative stress and deregulation of signalling cascades and how natural products can be used tactfully to protect against UV induced harmful effects.

Breakpoint cluster region-c-abl oncogene 1, non-receptor tyrosine kinase signaling: current patterns of the versatile regulator revisited.

Increasing sophisticated information suggests that cancer cells express constitutively active oncogenic kinases such as breakpoint cluster region- c-abl oncogene 1, non-receptor tyrosine kinase (BCR-ABL1) that promote carcinogenesis independent of extrinsic growth factors. It is a well-established fact that through the aberrant activation of BCR-ABL1 signal transduction cascade, the perception of cellular growth signals becomes disconnected from the processes promoting cell growth, and this underlies the pathophysiology of leukemia. In this particular review we discuss the oncogenes and tumor suppressors comprising the regulatory network upstream and downstream of BCR-ABL1 and dismantle how derailed BCR-ABL1 signaling provides cell a selective growth advantage. Besides, we discuss why activation of BCR-ABL1, as an outcome of distinct oncogenic events, results in miscellaneous clinical outcomes, and how the intricacy of the BCR-ABL1 signaling network might dictate therapeutic approaches. In this review, our current comprehension of BCR-ABL1 signaling will be summarized.

BCR-ABL1 in leukemia: disguise master outplays riding shotgun.

Leukemia is a many-sided molecular disorder that arises because of over expression of oncogenes, suppression of tumor suppressor genes, and chromosomal translocations. These chromosomal rearrangements are nonetheless among the many determinants that underlie transformation of cells from normal to a cancerous phenotype and predispose cells to refractoriness against interventions by reduced drug influx and substantial drug efflux. This review unfolds current understanding of BCR-ABL1 (break point cluster region-c-abl oncogene 1, non-receptor tyrosine kinase) signaling with a focus on apoptotic suppressive mechanisms and alternative approaches to chronic myeloid leukemia therapy.